Display driver circuit board and display device

ABSTRACT

A display driver circuit board includes: a substrate connected to a display panel; a display driver mounted on the substrate, and processing an input signal and output an image signal; and a terminal including a plurality of unit terminals arranged in a join, of the substrate, to the display panel, the unit terminals including a unit terminal supplying the image signal to the display panel. The substrate includes: the terminal including a plurality of terminals arranged at intervals in the join; and a no-terminal-formation region provided between the terminals neighboring, and keeping the unit terminals from being formed.

CROSS-REFERENCE TO RELATED APPLICATION

The present application claims priority to U.S. Provisional ApplicationSer. No. 62/924,578, filed Oct. 22, 2019, the content to which is herebyincorporated by reference into this application.

BACKGROUND OF THE INVENTION 1. Field of the Invention

This specification discloses a technique directed to a display drivercircuit board and a display device.

2. Description of the Related Art

Japanese Unexamined Patent Application Publication No. 2008-033094 citesa typical example of display devices known in the art. A display devicecited in Japanese Unexamined Patent Application Publication No.2008-033094 includes: a display panel including a display driver circuitboard provided with a drive electrode and having a back face providedwith an ejector of a drive electrode line to be electrically connectedto the drive electrode, a transparent electrode substrate, and a displayunit held between the display driver circuit board and the transparentelectrode substrate; and a display driver circuit board mountingsubstrate including an electrode electrically connected through anelectric connector to the ejector, of the drive electrode line, providedto the display driver circuit board.

SUMMARY OF THE INVENTION

In the display device cited in Japanese Unexamined Patent ApplicationPublication No. 2008-033094, the back face of the substrate can be usedas a region for connecting to the driver circuit, and, furthermore, alarge terminal can be connected. Such a configuration makes it possibleto increase connection density. Japanese Unexamined Patent ApplicationPublication No. 2008-033094 adopts, however, a significantly specialstructure in which the display driver circuit board has a via holeformed therethrough in order to connect the drive electrode on thedisplay driver circuit board to the electrode on the back face of thedisplay driver circuit board. Such a structure inevitably decreasessealability caused by the via hole. In addition, because of thisstructure, currently working production facilities need to be replacedwith new ones. Manufactures of display devices are asked to provide thedisplay devices with higher definition, without adopting such a specialstructure.

A technique cited in this Specification is devised under the abovecircumstances, and is intended to provide a display with high definitionwithout adopting a special structure.

(1) A display driver circuit board according to a technique described inthe Specification of the present application includes: a substrateconnected to a display panel; a display driver mounted on the substrate,and processing an input signal and output an image signal; and aterminal including a plurality of unit terminals arranged in a join, ofthe substrate, to the display panel, the unit terminals including a unitterminal supplying the image signal to the display panel, wherein thesubstrate includes: a plurality of the terminals arranged at intervalsin the join; and a no-terminal-formation region provided between theterminals neighboring, and keeping the unit terminals from being formed.

(2) In addition to the above item (1), in the display driver circuitboard, in the substrate, the join may be divided for each of theterminals.

(3) In addition to the above item (2), in the display driver circuitboard, in the substrate, the no-terminal-formation region may be anotch.

(4) In addition to any one of the above items (1) to (3), in the displaydriver circuit board, in each of the terminals, the unit terminals mayinclude a common potential terminal supplied with a common potentialsignal, and a plurality of the common potential terminals may be eachdisposed at an end, of the join of the substrate, along the arrangementof the terminals, and in a portion, of the join of the substrate,bordering the no-terminal-formation region.

(5) In addition to any one of the above items (1) to (4), in the displaydriver circuit board, the display driver may include a plurality ofgroups of input terminals receiving the input signal, each of the groupsincluding a pair of the input terminals.

(6) In addition to the above item (5), in the display driver circuitboard, where “n” is the number of the unit terminals included in theterminals and receiving the image signal to be output from the displaydriver, and “m” is a group number counted from a first group of thegroups of the input terminals, the first group of the input terminalsmay be sequentially supplied with a 0th to an (n−1)th input signalsincluded in the input signal, and an m-th group of the input terminalsmay be sequentially supplied with an n·(m−1)th to an (n·m−1)th inputsignals included in the input signal.

(7) In addition to any one of the above items (1) to (6), in the displaydriver circuit board, the display driver may be disposed across theno-terminal-formation region along the arrangement of the terminals.

(8) In addition to any one of the above items (1) to (6), the displaydriver circuit board may further include as many display drivers,included in the display driver, as the terminals.

(9) A display device according to a technique described in theSpecification of the present application includes: the display drivercircuit board according to any one of the items (1) to (8); and adisplay panel to which the display driver circuit board is connected.

A technique cited in this specification can provide a display with highdefinition without adopting a special structure.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a plan view illustrating a display driver circuit board,according to a first embodiment, connected to a liquid crystal panel.

FIG. 2 is a circuit diagram illustrating pixels arranged in a displayarea of an array substrate included in the liquid crystal panel.

FIG. 3 is a bottom view of a source driver included in the displaydriver circuit board.

FIG. 4 is a plan view of the display driver circuit board.

FIG. 5 is a plan view of a join of the display driver circuit board inthe liquid crystal panel.

FIG. 6 is a plan view of a display driver circuit board, according to asecond embodiment, positioned on the far left of a liquid crystal panel.

FIG. 7 is a plan view of a display driver circuit board positioned onthe far right of the liquid crystal panel.

FIG. 8 is a plan view of a display driver circuit board positionedtoward the center of the liquid crystal panel.

FIG. 9 is a bottom view of a source driver included in a display drivercircuit board according to a third embodiment.

FIG. 10 is a plan view of a display driver circuit board.

FIG. 11 is a drawing to illustrate how to distribute signals to be inputto a source driver.

FIG. 12 is a plan view of a display driver circuit board according to afourth embodiment.

FIG. 13 is a plan view of a display driver circuit board according to afifth embodiment.

FIG. 14 is a plan view of a display driver circuit board according to asixth embodiment.

DETAILED DESCRIPTION OF THE INVENTION First Embodiment

A first embodiment is described, with reference to FIGS. 1 to 5.Described as an example in this embodiment is a display driver circuitboard 20 connected to a liquid crystal panel (a display panel) 10. Notethat a part of each drawing includes an illustration of an X-axis, aY-axis, and a Z-axis, so that the directions of the axes correspond todirections indicated in the drawing.

The liquid crystal panel 10 displays an image, using light to be emittedfrom a backlight device (a lighting device). Together with the backlight device, the liquid crystal panel 10 constitutes a liquid crystaldisplay device (a display device) LCD. The liquid crystal panel 10illustrated in FIG. 1 is shaped into a rectangle in horizontalorientation. In the liquid crystal panel 10, the center of the screen isa display area (an active area) AA capable of displaying an image;whereas, the outer edge of the screen is a non-display area (anon-active area) NAA shaped into a frame (a photo-frame) in planner viewto surround the display area AA, and displaying no image. The liquidcrystal panel 10 according to this embodiment is assumed to have ascreen size of, for example, approximately 32 inches and a resolution ofapproximately “7,680×4,320 pixels” equivalent to an 8K resolution. Inthe liquid crystal panel 10 whose screen size is approximately 32inches, the display area AA has a long side dimension of approximately700 mm and a short side dimension of approximately 400 mm. In thisembodiment, the long-side direction of the liquid crystal panel 10corresponds to the X-axis direction of each drawing, the short-sidedirection to the Y-axis direction, and a thickness-direction to theZ-axis direction. Note that, in FIG. 1, the display area AA issurrounded by a dot-and-dash line.

The liquid crystal panel 10 includes: a pair of substrates 10A and 10Bmade of substantially transparent (light-transparent) glass; and aliquid crystal layer held between the substrates 10A and 10B. The liquidcrystal layer contains liquid crystal molecules, that is, a substancewhose optical property changes when a voltage is applied. Of the pair ofsubstrates 10A and 10B, the substrate 10A on the front face (in thefront) is a CF substrate (a counter substrate) 10A, and the substrate10B on the rear face (in the back) is an array substrate (an activematrix substrate) 10B. The CF substrate 10A, which has a short sidedimension shorter than that of the array substrate 10B, is attached tothe array substrate 10B such that Y-axis-ends of the short sides of theCF substrate 10A (upper ends of the short sides of the CF substrate 10Ain FIG. 1) coincide with Y-axis-ends of the short sides of the arraysubstrate 10B. Hence, the other Y-axis-ends of the short sides of thearray substrate 10B (lower ends of the short sides of the arraysubstrate 10B) do not overlap with the CF substrate 10A. The other endsare referred to as a CF substrate non-overlapping portion 10B1. The CFsubstrate non-overlapping portion 10B1 is a strip of region extendingalong the X-axis. Mounted on this CF substrate non-overlapping portion10B1 is an end of a display driver circuit board 20 for transmittingvarious signals to the liquid crystal panel 10. The display drivercircuit board 20 will be described later in detail.

As illustrated in FIG. 2, the array substrate 10B has an interior face,in the display area AA, provided with: a plurality of gate lines(scanning lines) 11 and a plurality of source lines (signal lines, datalines) 12 arranged in a matrix; and TFTs 13 acting as switching elementsand pixel electrodes 14 each provided to a corresponding one ofintersections between the gate lines 11 and the source lines 12. Thegate lines 11 extend along the X-axis across the display area AA andconnect to gate electrodes of the TFTs 13; whereas, the source lines 12extend along the Y-axis across the display area AA and connect to sourceelectrodes of the TFTs 13. The gate lines 11 are spaced apart from eachother and arranged along the Y-axis; whereas, the source lines 12 arespaced apart from each other and arranged along the X-axis. The TFTs 13and the pixel electrodes 14 are arranged planarly along the X-axis andthe Y-axis in a matrix. Each of the TFTs 13 has a drain electrodeconnected to a corresponding one of the pixel electrodes 14. The TFTs 13are driven in accordance with a scanning signal to be supplied to thegate lines 11. When the TFTs 13 are driven, the pixel electrodes 14 arecharged with a potential in accordance with an image signal to besupplied to the source lines 12.

In contrast, as illustrated in FIG. 2, the CF substrate 10A has aninterior face, in the display area AA, provided with: color filters inthree colors of red (R), green (G), and blue (B) each arranged tooverlap a corresponding one of the pixel electrodes 14; and lightshields (black matrices) each dividing neighboring color filters. Notethat, in FIG. 2, an alphabet (R, G, B) is assigned to each of the pixelelectrodes 14 to represent a color of a color filter overlapping thecorresponding pixel electrode 14. In this liquid crystal panel 10, colorfilters R, G, B arranged along the X-axis and three pixel electrodes 14each facing a corresponding one of the color filters R, G, B constitutepixels PX in respective three colors. Then, in this liquid crystal panel10, the pixels PX arranged side-by-side along the X-axis and providedwith respective three colors R, G, B, constitute a display pixel capableof providing colors in a predetermined grayscale. Each of the pluralityof the pixels PX are arranged along the X-axis and the Y-axis in amatrix. The liquid crystal panel 10 according to this embodiment hasapproximately an 8K resolution. Hence, “7,680” display pixels and“23,040” pixels PX (the source lines 12) are arranged along the X-axis.Moreover, “4,320” display pixels and pixels PX (the gate lines 11) arearranged along the Y-axis. Furthermore, either the CF substrate 10A orthe array substrate 10B is provided with a common electrode made of atransparent electrode material similar to that of the pixel electrode14, and disposed to be spaced apart from, and overlap, the pixelelectrode 14. The common electrode is maintained to have a commonpotential (a reference potential). In the liquid crystal panel 10, apredetermined electric field is applied to the liquid crystal layer inaccordance with a potential difference that occurs between this commonelectrode and the corresponding pixel electrode 14. Such a feature makesit possible to cause each pixel PX to provide a predetermined grayscale.

The display driver circuit board 20 will be described in detail. Asillustrated in FIG. 1, the display driver circuit board 20 includesdisplay driver circuit boards 20 linearly arranged along the X-axis andmounted on the CF substrate non-overlapping portion 10B1. In thisembodiment, “12” display driver circuit boards 20 are mounted (arranged)on the liquid crystal panel 10. For the sake of mounting, theneighboring display driver circuit boards 20 are arranged atpredetermined intervals (e.g., approximately 3 mm intervals). Each ofthe display driver circuit boards 20 includes a substrate 21 made of asynthetic resin material (e.g., polyimide-based resin) and shaped into aflexible film sheet. In planner view, the substrate 21 is shaped into asubstantial rectangle in horizontal orientation. On a surface of thesubstrate 21, a source driver (a display driver) 22 is mounted and manywires are patterned and routed. In this embodiment, “one” source driver22 is mounted on the substrate 21. The source driver 22 is mounted onthe substrate 21 in the form of a chip-on-film (COF) package. The sourcedriver 22 is an LSI chip containing a driver circuit, and capable ofprocessing an input signal and outputting an image signal. The inputsignal to be input into the source driver 22 is supplied from a signalsupply source (e.g., a control substrate) connected to an end of thedisplay driver circuit board 20. The image signal output from the sourcedriver 22 is supplied to the liquid crystal panel 10 to which anotherend of the display driver circuit board 20 is connected. In the liquidcrystal panel 10, the image signal is supplied to the source lines 12(see FIG. 2).

In the liquid crystal panel 10, as illustrated in FIG. 1, each of thesource drivers 22 mounted on a corresponding one of the display drivercircuit boards 20 arranged along the X-axis supplies image signals in astrip area, of the display area AA of the liquid crystal panel 10, witha predetermined width along the X-axis. Specifically, the long sidedimension of the display area AA is divided by the number of the sourcedrivers 22 installed, and a dimension is obtained. The obtaineddimension is the width dimension of the strip area assigned to onesource driver 22. Each source driver 22 is assigned to the strip area tosupply the strip area with image signals. In this embodiment, “23,040”pixels PX (the source lines 12) are arranged along the X-axis in theliquid crystal panel 10. Hence, one source driver 22 is required tooutput “1,920” image signals. This is the number of output channelsassigned to each of the source drivers 22. Other than the input signalto be input to the source driver 22 and the image signal to be outputfrom the source driver 22, a wiring pattern of the substrate 21 iscapable of transmitting various signals (including, for example, a gatestart pulse signal, a clock signal, a reset signal that are hereinafterreferred to as a “gate signal”) related to a scanning signal to besupplied to the gate lines 11, a common potential signal to be suppliedto the common electrode, and a power supply voltage. The gate signal,the common potential signal, and the power supply voltage are suppliedfrom the signal supply source to the display driver circuit board 20;however, these signals are supplied to the liquid crystal panel 10 notthrough the source driver 22. Note that, mounted on the liquid crystalpanel 10 is a gate driver to process the gate signal and output thescanning signal. A similar function is provided to a gate drivermonolithic (GDM) circuit monolithically included in the liquid crystalpanel 10.

The source driver 22 has an opposing face to the substrate 21. Asillustrated in FIG. 3, the opposing face is provided with a plurality ofinput terminals 22A and a plurality of output terminals 22B. The inputterminals 22A are supplied with such a signal as an input signaltransmitted through the wiring pattern of the substrate 21; whereas, theoutput terminals 22B are supplied with an image signal to be output fromthe source driver 22. Each pair of the input terminals 22A constitutes agroup to be supplied with input signals to be processed by the sourcedriver 22. Each pair of the input terminals 22A constituting a group issupplied with input signals for image signals to be supplied to “640”display pixels arranged along the X-axis, that is, to be supplied tosource lines 12 connected to “1,920” pixels PX arranged along theX-axis. Distribution (data mapping) of the input signals among thesource drivers 22 is specifically described as follows: The sourcedriver 22, which is in the display driver circuit board 20 positioned onthe far left in FIG. 1, includes pairs of input terminals 22Asequentially supplied with the 0th to the 1,919th input signals. Thesource driver 22, which is in the display driver circuit board 20positioned second from the left in FIG. 1, includes pairs of inputterminals 22A sequentially supplied with the 1,920th to the 3,839thinput signals. The source driver 22, which is in the display drivercircuit board 20 positioned twelfth from the far left, that is,positioned on the far right in FIG. 1, includes pairs of input terminals22A sequentially supplied with the 21,120th to the 23,039th inputsignals. That is, the pairs of the input terminals 22A included in thesource driver 22 of a display driver circuit board 20 are sequentiallysupplied with the “Y·(X−1)th” to the “X·(Y−1)th” input signals, where“X” is what number the display driver circuit board 20 is from the farleft in FIG. 1, and “Y” is the number of output channels of the sourcedriver 22. Moreover, there are as many output terminals 22B installed asthe output channels of each source driver 22.

Meanwhile, as illustrated in FIG. 4, a mounting region of the sourcedriver 22 on the substrate 21 is provided with a plurality of driverinput terminals 23 and a plurality of driver output terminals 24respectively connected to the input terminals 22A and the outputterminals 22B through, for example, anisotropic conductive film. Thedriver input terminals 23 are positioned along the X-axis and offsetaway from the liquid crystal panel 10 in relation to a group of thedriver output terminals 24 of the substrate 21. As many driver inputterminals 23 as the input terminals 22A of the source driver 22 arearranged at intervals along the X-axis. The driver output terminals 24are positioned along the X-axis and offset toward the liquid crystalpanel 10 in relation to a group of the driver input terminals 23 of thesubstrate 21. As many driver output terminals 24 as the output terminals22B of the source driver 22 are arranged at intervals along the X-axis.Connected to the driver input terminals 23 and the driver outputterminals 24 is wiring patterned and routed on the substrate 21.Moreover, a plurality of signal supply source terminals 25 are providedto a join, on the substrate 21, to be connected to the signal supplysource. The signal supply source terminals 25 are arranged at intervalsalong the X-axis.

As illustrated in FIG. 5, the CF substrate non-overlapping portion 10B1of the array substrate 10B included in the liquid crystal panel 10 isprovided with a panel terminal 15 including a plurality of panel unitterminals 15A. The panel terminal 15 is disposed to a join, of the CFsubstrate non-overlapping portion 10B1, to a display driver circuitboard 20. The panel terminal 15 includes a plurality of panel terminals15 arranged along the X-axis at predetermined intervals (approximately 3mm). The number of the panel terminals 15 arranged is twice as many asthe number of the display driver circuit boards 20 to be mounted (24display driver circuit boards 20). Each of the panel terminals 15 has anX-axis dimension obtained as follows: The long-side dimension(approximately 700 mm) of the display area AA is divided by the number(24) of the panel terminals 15, and a value is obtained (approximately29 mm). From the obtained value, an interval between neighboring panelterminals 15 is subtracted, and a value obtained (approximately 26 mm)is the X-axis dimension of each panel terminal 15. The panel unitterminals 15A included in the panel terminals 15 are linearly arrangedat intervals along the X-axis. An interval between neighboring panelunit terminals 15A is significantly shorter (the order of micrometers)than that between neighboring panel terminals 15. Each of the panel unitterminals 15A receives such signals as the image signal, the gatesignal, the common potential signal, and the power source voltagesupplied from the display driver circuit board 20. Of the panel unitterminals 15A, “960” panel unit terminals 15A, that is, a half as manyas the number of the output channels of the source driver 22, receiveimage signals.

In contrast, the substrate 21 in the display driver circuit board 20includes a join 21A to be connected to the liquid crystal panel 10. Asillustrated in FIG. 4, arranged in the join 21A is a terminal 26including a plurality of unit terminals 26A. The terminal 26 has anX-axis dimension as long as the X-axis dimension of the panel terminal15 (approximately 26 mm). The unit terminals 26A included in theterminal 26 are linearly arranged at intervals along the X-axis. Aninterval between neighboring unit terminals 26A is significantly shorter(the order of micrometers) than that between neighboring terminals 26.Each of the unit terminals 26A is connected through anisotropicconductive film to a corresponding one of the panel unit terminals 15Aincluded in the above panel terminals 15. The unit terminals 26A includeat least: an image signal terminal 26A1 supplied with the image signal;a common potential terminal 26A2 supplied with the common potential; agate signal terminal 26A3 supplied with the gate signal; and a powersource voltage terminal 26A4 supplied with the power source voltage. Asmany as “960” image signal terminals 26A1 are included in the terminal26, that is, the number of the image signal terminals 26A1 is half asmany as the number of the output channels of the source driver 22. Theimage signal terminals 26A1 are arranged side-by-side in the center ofthe join 21A along the X-axis. Moreover, the common potential terminal26A2, the gate signal terminal 26A3, and the power supply voltageterminal 26A4 are provided to each of opposing ends 21A1 of the join 21Aalong the X-axis.

As illustrated in FIG. 4, the terminal 26 includes two terminals 26. Inthe join 21A of the substrate 21, the two terminals 26 are arranged atan interval along X-axis. The interval between the two terminals 26 isapproximately the same as the intervals between the neighboring panelterminals 15 (approximately 3 mm), and also is approximately the same asthe intervals between the neighboring display driver circuit boards 20(approximately 3 mm). Then, the join 21A of the substrate 21 includes ano-terminal-formation region 27 provided between the neighboringterminals 26, and keeping the unit terminal 26A from being formed. Theno-terminal-formation region 27 has an X-axis dimension (a dimension inwhich the terminals 26 are arranged) matching the interval between theneighboring terminals 26. The X-axis dimension is significantly largerthan the intervals between the neighboring unit terminals 26A. Thesubstrate 21 has an X-axis dimension obtained as follows: The X-axisdimension of the terminal 26 (approximately 26 mm) is multiplied by “2”that is the number of terminals 26, and a value is obtained. Theobtained value is added to the X-axis dimension of theno-terminal-formation region 27 (approximately 3 mm), and a value isobtained (approximately 55 mm). The obtained value is the X-axisdimension of the substrate. 21.

Here, typically, each of the display driver circuit boards is connectedto a corresponding one of the panel terminals 15 of the liquid crystalpanel 10. Hence, each display driver circuit board is provided with oneterminal. In this case, the number of the display driver circuit boardsis “24” that is the same as the number of the panel terminals 15.Furthermore, the number of the output channels of the source driver tobe mounted on the display driver circuit board is “960.” Hence, thelargest X-axis dimension acceptable of the display driver circuit boardis obtained as follows: The long side dimension of the display area AA(approximately 700 mm) is divided by the number of the display drivercircuit boards (24), and a value is obtained (approximately 29 mm). Fromthe obtained value, an interval (approximately 3 mm) between theneighboring display driver circuit boards is subtracted, and a value isobtained (approximately 26 mm). The obtained value is the largest X-axisdimension acceptable. When wiring is patterned on the display drivercircuit board having such a dimension with the source driver mountedthereon, the number of the output channels is excessively large. Hence,it is difficult to design all the wiring patterns to be fitted in thesubstrate in view of arrangement space.

In this regard, as illustrated in FIG. 4, the join 21A, to the liquidcrystal panel 10, in the substrate 21 of the display driver circuitboard 20 includes the no-terminal-formation region 27 between the twoterminals 26 arranged at an interval. Such a feature allows one displaydriver circuit board 20 to be connected to a portion of the liquidcrystal panel 10 instead of two display driver circuit boards astypically connected, and furthermore, two panel terminals 15 to beconnected to two terminals 26 in the liquid crystal panel 10 can be leftas they are. Hence, the X-axis dimension of the substrate 21 is obtainedas follows: A value twice as large as the X-axis dimension of a typicaldisplay driver circuit board (approximately 26 mm) is added to aninterval (approximately 3 mm) between typical two neighboring displaydriver circuit boards, and a value is obtained (approximately 55 mm).The obtained value is the X-axis dimension of the substrate 21. Such afeature makes it possible to leave a large space for wiring to bepatterned on the substrate 21 by the interval (approximately 3 mm) leftbetween the neighboring typical display driver circuit boards,beneficially achieving high definition. Moreover, the feature eliminatesthe need for changing the design of the panel terminals 15 acting asjoins, of the liquid crystal panel 10, to the terminals 26.

Then, the substrate 21 illustrated in FIG. 4 is bifurcated so that thejoin 21A to the liquid crystal panel 10 is divided for each of theterminals 26. The join 21A of the substrate 21 includes a notch 21Bformed between the two terminals 26. That is, the no-terminal-formationregion 27 is the notch 21B. The notch 21B, which is shaped into a squarein planner view, has an X-axis dimension matching an interval betweenthe neighboring terminals 26, that is, an X-axis dimension of theno-terminal-formation region 27. This means that the entireno-terminal-formation region 27 is the notch 21B. Here, when connectedto the liquid crystal panel 10, the join 21A of the substrate 21 isheated and pressed with anisotropic conductive film provided between thejoin 21A and the liquid crystal panel 10. Hence, the join 21A of thesubstrate 21 thermally expands, and the thermal expansion might causemisalignment along the X-axis between the unit terminals 26A of theterminals 26 and the panel unit terminals 15A of the panel terminals 15.In this case, too, the join 21A of the substrate 21 to the liquidcrystal panel 10 is divided for each of the terminals 26. Even if theunit terminals 26A are misaligned along the X-axis because of thethermal expansion of the join 21A, the misalignment is not significant.Specifically, when the substrate 21 has a thermal expansion rate of, forexample, 0.3%, an amount of misalignment to be assumed if the join isnot divided is approximately 16.5 μm; whereas, the amount ofmisalignment to be assumed of the join 21A in a divided structure halvesto be approximately 7.8 μm. Such a feature reduces the risk of poorelectrical connection. Moreover, the no-terminal-formation region 27 isformed of the notch 21B, such that, using an edge of the notch 21B ofthe join 21A, the join 21A is easily positioned with respect to theliquid crystal panel 10. Such a feature makes it possible to easilyconnect the substrate 21 to the liquid crystal panel 10. Moreover,compared with a case where the join of the substrate is divided by aslit, the notch 21B provides a clearance between the divided portions ofthe join 21A, reducing interference between the divided portions andfurther facilitating joining work.

As illustrated in FIG. 4, the source driver 22 mounted on the substrate21 structured above is disposed along the X-axis across theno-terminal-formation region 27. Specifically, the source driver 22 isshaped into a rectangle in horizontal orientation along the X-axis, anddisposed with the center line substantially aligned along the X-axiswith that of the substrate 21. Here, if two source driver each having960 output channels are mounted on the substrate, the two source drivershave to be spaced apart from each other at a predetermined interval forthe sake of mounting. In contrast, one source driver 22 having 1,920output channels is disposed along the X-axis across theno-terminal-formation region 27. Such a feature makes it possible toleave a large space along the X-axis for wiring to be patterned on bothsides of the source driver 22 in the substrate 21. Hence, the featureachieves high definition more beneficially.

As can be seen, the display driver circuit board 20 of this embodimentincludes: the substrate 21 connected to the liquid crystal panel (adisplay panel) 10; the source driver (a display driver) 22 mounted onthe substrate 21, and processing an input signal and outputting an imagesignal; and the terminal 26 including the unit terminals 26A arranged inthe join 21A, of the substrate 21, to the liquid crystal panel 10, theunit terminals 26A including a unit terminal 26A supplying the imagesignal to the liquid crystal panel 10, wherein, the substrate 21includes: the terminal 26 including the terminals 26 arranged atintervals in the join 21A; and the no-terminal-formation region 27provided between the terminals 26 neighboring and keeping the unitterminals 26A from being formed.

According to such features, the source driver 22 processes the inputsignal and outputs the processed input signal as the image signal. Theimage signal is supplied through the terminal 26 including the unitterminals 26A disposed in the join 21A, of the substrate 21, to theliquid crystal panel 10. The image signal displays an image on theliquid crystal panel 10.

A typical display device has a special structure in which the displaydriver circuit board includes a via hole formed therethrough to achievehigh definition. In order to avoid such a special structure, adopted isa common structure in which a plurality of display driver circuit boardsare arranged with respect to the liquid crystal panel 10. In such acase, for the sake of mounting, the neighboring display driver circuitboards are spaced apart from each other at predetermined intervals orgreater. Hence, if more display driver circuit boards are connected toachieve higher definition, each display driver circuit board is likelyto be smaller in acceptable external dimensions in relation to theexternal dimensions of the liquid crystal panel 10. The smaller externaldimensions make it difficult to leave a space in the substrate 21 forproviding, for example, wiring.

In contrast, the join 21A, of the substrate 21, to the liquid crystalpanel 10 includes the terminals 26 including the unit terminals 26A andarranged at intervals. In addition, provided between the terminals 26 isthe no-terminal-formation region 27 keeping the unit terminals 26A frombeing formed. Such features allows one display driver circuit board 20to be connected to a portion of the liquid crystal panel 10 instead oftwo or more display driver circuit boards as typically connected, and,furthermore, the configuration of the portion, of the liquid crystalpanel 10, to be connected to the terminals 26 can be left as it is. Thefeatures make it possible to leave a large space for wiring to bedisposed on the substrate 21 by the interval left between theneighboring typical display driver circuit boards, beneficiallyachieving high definition. Hence, the display device of the presentdisclosure can achieve high definition with neither adopting a specialstructure as typically seen, nor changing the design of the join, of theliquid crystal panel, to the terminal 26.

Moreover, in the substrate 21, the join 21A is divided for each of theterminals 26. When the substrate 21 is connected to the liquid crystalpanel 10, the join 21A to the liquid crystal panel 10 is typicallyheated. Because of this heating, the join 21A thermally expands. In thiscase, too, the join 21A of the substrate 21 to the liquid crystal panel10 is divided for each of the terminals 26. Even if the unit terminals26A are misaligned because of the thermal expansion of the join 21A, themisalignment is not significant. Such a feature reduces the risk of poorelectrical connection.

Moreover, in the substrate 21, the no-terminal-formation region 27 isthe notch 21B. Using an edge of the notch 21B, the join 21A of thesubstrate 21 is easily positioned with respect to the liquid crystalpanel 10. Such a feature makes it possible to easily connect thesubstrate 21 to the liquid crystal panel 10.

Furthermore, the source driver 22 is disposed across theno-terminal-formation region 27 along the arrangement of the terminals26. Compared with a case where source drivers are arranged at intervals,the disposition of the source driver 22 makes it possible to leave alarge space for wiring to be disposed on both sides of the source driver22 in the substrate 21 along the arrangement of the terminals 26. Hence,the feature achieves high definition more beneficially.

In addition, the liquid crystal display device (the display device) LCDaccording to this embodiment includes, as described above, the displaydriver circuit board 20 and the liquid crystal panel (a display panel)10 to which the display driver circuit board 20 is connected. The liquidcrystal display device LCD including such a feature is beneficial inachieving high definition of the liquid crystal panel 10 to which thedisplay driver circuit board 20 is connected.

Second Embodiment

A second embodiment will be described, with reference to FIGS. 6 to 8.This second embodiment describes changes in, for example, arrangement ofcommon potential terminals 126A2. Note that identical or substantiallyidentical structures and advantageous effects between the firstembodiment and this embodiment will not be elaborated upon.

As illustrated in FIGS. 6 to 8, terminals 126 according to thisembodiment are different in arrangement of unit terminals 126A,depending on a display driver circuit board 120 to be installed. FIG. 6is a plan view of a display driver circuit board 120E positioned on thefar left of the liquid crystal panel 10 illustrated in FIG. 1. FIG. 7 isa plan view of a display driver circuit board 120E positioned on the farright of the liquid crystal panel 10 illustrated in FIG. 1. FIG. 8 is aplan view of a display driver circuit board 120C positioned in thecenter other than the far left and the far right of the liquid crystalpanel 10 illustrated in FIG. 1. Note that, in order to distinguishbetween display driver circuit boards 120, a display driver circuitboard positioned at an either end of the liquid crystal panel 10illustrated in FIG. 1 is denoted with a reference sign having a suffix“E”, and a display driver circuit board positioned in the center otherthan either end of the liquid crystal panel 10 is denoted with areference sign having a suffix “C.” In order to collectively refer tothe display driver circuit boards 120, no suffix is added to thereference sign.

FIG. 6 shows the display driver circuit board 120E positioned on the farleft of the liquid crystal panel 10 illustrated in FIG. 1. Specifically,as illustrated in FIG. 6, a unit terminal 126A in a terminal 126includes a gate signal terminal 126A3 and a power source voltageterminal 126A4 arranged side by side at one of opposing ends 121A1, onthe left in FIG. 6, of a join 121A of the substrate 121, that is, theopposing end 121A1 positioned closer to an end of the liquid crystalpanel 110. In contrast, a common potential terminal 126A2 is disposed atone of the opposing ends 121A1, on the far right in FIG. 6, of the join121A of the substrate 121, that is, the opposing end 121A1 closer to thecenter of the liquid crystal panel 110. In addition, a common potentialterminal 126A2 is also disposed in a portion 121A2 bordering ano-terminal-formation region 127 (a notch 121B) of the join 121A.Meanwhile, FIG. 7 shows a display driver circuit board 120E positionedon the far right of the liquid crystal panel 10 illustrated in FIG. 1.As illustrated in FIG. 7, a unit terminal 126A in a terminal 126includes a gate signal terminal 126A3 and a power source voltageterminal 126A4 arranged side by side at one of opposing ends 121A1, onthe far right in FIG. 7, of a join 121A of the substrate 121, that is,the opposing end 121A1 positioned closer to an end of the liquid crystalpanel 110. In contrast, a common potential terminal 126A2 is disposed atone of the opposing ends 121A1, on the far left in FIG. 7, of the join121A of the substrate 121, that is, the opposing end 121A1 closer to thecenter of the liquid crystal panel 110. In addition, a common potentialterminal 126A2 is also disposed in a portion 121A2 bordering ano-terminal-formation region 127 (a notch 121B) of the join 121A. As canbe seen, in the display driver circuit board 120E, the common potentialterminal 126A2 of the terminal 126, which is disposed closer to an endof the liquid crystal panel 110 with respect to theno-terminal-formation region 127, is disposed only at an end closer tothe no-terminal-formation region 127; whereas, the common potentialterminal 126A2 of the terminal 126, which is disposed closer to thecenter of the liquid crystal panel 110 with respect to theno-terminal-formation region 127, is disposed at each end along theX-axis. That is, in the display driver circuit board 120E, the commonpotential terminals 126A2 are distributed among three positions spacedapart from each other along the X-axis in the join 121A of the substrate121.

Then, FIG. 8 shows the display driver circuit board 120C positionedcloser to the center, other than the far left and the far right, of theliquid crystal panel 110 illustrated in FIG. 1. As illustrated in FIG.7, a unit terminal 126A in the terminal 126 does not include either thegate signal terminal 126A3 or the power source voltage terminal 126A4.That is, in the display driver circuit board 120C, the unit terminal126A includes the image signal terminal 126A1 and the common potentialterminal 126A2. The common potential terminal 126A2 is disposed at eachof opposing ends 121A1 of a join 121A of a substrate 121. In addition,the common potential terminal 126A2 is also disposed in a portion 121A2bordering a no-terminal-formation region 127 (a notch 121B) of the join121A. Hence, in the display driver circuit board 120C, the commonpotential terminals 126A2 are each disposed along the X-axis at aneither end of the two terminals 126 arranged to sandwich theno-terminal-formation region 127. In other words, the common potentialterminals 126A2 are distributed among four positions spaced apart fromeach other along the X-axis in the join 121A of the substrate 121.

Here, in the configuration described in the first embodiment, the commonpotential terminals 26A2 are arranged only at the opposing ends 21A1 ofthe join 21A, that is, only in two positions spaced apart from eachother along the X-axis. (See FIG. 4.) Compared with such aconfiguration, the display driver circuit boards 120, in FIGS. 6 to 8,according to this embodiment each have the common potential terminals126A2 distributed among three or four positions spaced apart from eachother along the X-axis. That is, the common potential terminals in thisembodiment are distributed among more positions than those in the firstembodiment. Hence, the liquid crystal panel 110 to be connected to thesubstrate 121 can be supplied with the common potential signals in morepositions along the X-axis. Such a feature causes less imbalance indistribution of resistance in common potentials inside the face of theliquid crystal panel 110, and making it possible to beneficially obtainexcellent display quality.

As can be seen, according to this embodiment, the terminals 126 includethe common potential terminals 126A2 supplying a common potential signalto the unit terminals 126A. The common potential terminals 126A2 areeach disposed at the ends 121A1 and in the portions 121A2 included inthe join 121A of the substrate 121. The ends 121A1 are along thearrangement of the terminals 126, and the portions 121A2 boarder theno-terminal-formation region 127. Such a feature allows a commonpotential signal to be supplied to the liquid crystal panel 110 throughthe common potential terminals 126A2 included in the unit terminals126A. Here, compared with a typical substrate, the substrate 121 islarger along the arrangement of the terminals 126. However, the commonpotential terminals 126A2 are disposed at the ends 121A1 along the abovearrangement and in the portions 121A2 bordering theno-terminal-formation region 127 of the join 121A in the substrate 121.Compared with the case where the common potential terminals 126A2 arearranged only at the ends 121A1 along the arrangement, the liquidcrystal panel 110 to be connected to the substrate 121 receives commonpotential signals in more positions along the arrangement. Such afeature causes less imbalance in distribution of resistance in commonpotentials inside the face of the liquid crystal panel 110, and makingit possible to beneficially obtain excellent display quality.

Third Embodiment

A third embodiment will be described, with reference to FIGS. 9 to 11.This third embodiment describes a change from the first embodiment indistribution (data mapping) of signals to be input into a source driver222. Note that identical or substantially identical structures andadvantageous effects between the first embodiment and this embodimentwill not be elaborated upon.

As illustrated in FIG. 9, the source driver 222 according to thisembodiment includes input terminals 222A two groups of which, that is,four input terminals 222A in total, receive an input signal. Note that,in FIG. 9, among a plurality of input terminals 222A, shaded inputterminals 222A receive an input signal. Meanwhile, as illustrated inFIG. 10, a display driver circuit board 220 includes driver inputterminals 223 two groups of which, that is, four driver input terminals223 in total, are connected to the input terminals 222A to supply theinput terminals 222A with an input signal. Note that, in FIG. 10, amonga plurality of driver input terminals 223, shaded driver input terminals223 supply an input signal. This configuration doubles the number of theinput terminals 222A compared with that of the first embodiment.Accordingly, the number of input signals to be input per unit timedoubles. Such a feature provides twice as much time for processing theinput signals by the source driver 222 as that in the first embodiment,which is more beneficial in achieving high definition.

Described next is the distribution of signals to be input into thesource driver 222, with reference to FIG. 11. FIG. 11 shows the numbersin the order of the arrangement of the display driver circuit boards 220so that, in the liquid crystal panel 10 illustrated in FIG. 1, thedisplay driver circuit board 20 positioned on the far left is the firstone, and the display driver circuit board 20 positioned on the far rightis the twelfth one. FIG. 11 also shows attributes of the input signalsin the order of input. The input signals are supplied to the inputterminals 222A of the display driver circuit boards 220. As to theattributes of the input signals illustrated in FIG. 11, colors of pixelsincluded in display pixels are indicated with alphabets “R, G, B”, andthe display pixels are numbered so that a display pixel positioned onthe far left of the display area is a 0th display pixel and a displaypixel positioned on the far right of the display area is a 7,679thdisplay pixel. Note that, for the sake of the space, FIG. 11 selectivelyillustrates a part of the input signals to be distributed in the firstand the twelfth display driver circuit boards 220.

In this embodiment, as illustrated in FIG. 11, the first display drivercircuit board 220 includes a source driver 222 having two groups ofinput terminals 222A. A first group of input terminals 222A issequentially supplied with the 0th (R[0]) to the 959th (B[319]) inputsignals; whereas, a second group of input terminals 222A is sequentiallysupplied with the 960th (R[320]) to the 1,919th (B[639]) input signals.Accordingly, the second display driver circuit board 220 includes asource driver 222 having two groups of input terminals 222A. A firstgroup of input terminals 222A is sequentially supplied with the 1,920th(R[640]) to the 2,879th (B[959]) input signals; whereas, a second groupof input terminals 222A is sequentially supplied with the 2,880th(R[960]) to the 3,839th (B[1,279]) input signals. Accordingly, thetwelfth display driver circuit board 220 includes a source driver 222having two groups of input terminals 222A. A first group of inputterminals 222A is sequentially supplied with the 21,120th (R[7,040]) tothe 22,079th (B[7,359]) input signals; whereas, a second group of inputterminals 222A is sequentially supplied with the 22,080th (R[7,360]) tothe 23,039th (B[7,679]) input signals.

In general, where “n” is the number of unit terminals 226A included interminals 226 and receiving image signals to be output from the sourcedriver 222, “m” is a group number counted from the first group of thegroups of the input terminals 222A, and “X” is what number the displaydriver circuit board 20 is from the far left in FIG. 1, the first groupof the input terminals 222A is sequentially supplied with the 2n·(X−1)thto the (n·(2X−1)−1)th input signals; whereas, the m-th group of theinput terminals 222A is sequentially supplied with the n·(2X−1)·(m−1)thto the (n·(2Xm−2X−m+2)−1)th input signals. In particular, as to thefirst display driver circuit board 220, the first group of the inputterminals 222A is sequentially supplied with the 0th to the (n−1)thinput signals; whereas, the m-th group of the input terminals 222A issequentially supplied with the n·(m−1)th to the (n·m−1)th input signals.Such features make it possible to process the input signals by thesource driver 222 in the same order as that in the case where a displaydriver circuit board without a no-terminal-formation region 227 isconnected to a liquid crystal panel as typically seen. Hence, eventhough the display driver circuit board 220 has a special configurationincluding the no-terminal-formation region 227 and two groups of theinput terminals 222A, a standard according to transmission of inputsignals can be maintained as typically is, eliminating the need forintroducing a new standard.

As can be seen, according to this embodiment, the source driver 222includes a plurality of groups of the input terminals 222A receivinginput signals, each of the groups including a pair of the inputterminals 222A. Compared with a case where only one group of inputterminals is provided, the above configuration can increase the numberof input signals to be input per unit time. Such a feature makes itpossible to maintain as much time to process the input signals by thesource driver 222 as typically does.

Furthermore, where “n” is the number of unit terminals 226A included inthe terminals 226 and receiving image signals to be output from thesource driver 222, and “m” is a group number counted from the firstgroup of the groups of the input terminals 222A, the first group of theinput terminal 222A is sequentially supplied with the 0th to the (n−1)thinput signals, and the m-th group of the input terminal 222A issequentially supplied with the n·(m−1)th to the (n·m−1)th input signals.Such a feature allows the source driver 222 to process input signals tobe sequentially supplied to the groups of the input terminals 222A, andto output image signals. This source driver 222 processes the inputsignals in the same order as that in the case where a display drivercircuit board without the no-terminal-formation region 227 is connectedto a liquid crystal panel as typically seen. Hence, even though thedisplay driver circuit board 220 has a special configuration includingthe no-terminal-formation region 227 and a plurality of groups of theinput terminals 222A, a standard according to transmission of inputsignals can be maintained as typically is, eliminating the need forintroducing a new standard.

Fourth Embodiment

A fourth embodiment will be described, with reference to FIG. 12. Thisfourth embodiment describes a change from the first embodiment in thenumber of source drivers 322 included in a display driver circuit board320. Note that identical or substantially identical structures andadvantageous effects between the first embodiment and this embodimentwill not be elaborated upon.

As illustrated in FIG. 12, the display driver circuit board 320according to this embodiment has two source drivers 322 mounted thereon.The display driver circuit board 320 includes as many source drivers 322as terminals included in the display driver circuit board 320. Each ofthe source drivers 322 has “960” output channels the number of which isthe same as the number of unit terminals included in one terminal.Hence, one of the two source drivers 322 outputs image signals to besupplied to one of the two terminals, and the other one of the twosource drivers 322 outputs image signals to be supplied to the other oneof the two terminals. Such a configuration makes it possible to use thesame source driver 322 as the one used in the case where 24 displaydriver circuit boards, each including one source driver having “960”output channels, are connected to a liquid crystal panel as typicallyseen. This feature eliminates the need for introducing the sourcedrivers 322 as a dedicated component for the display driver circuitboard 320 having a special configuration including ano-terminal-formation region 327.

As can be seen, according to this embodiment, as may source drivers 322as terminals 326 are provided. Such a feature makes it possible to usethe same source driver 322 as the one used in the case where a displaydriver circuit board without the no-terminal-formation region 227 isconnected to a liquid crystal panel as typically seen. This featureeliminates the need for introducing the source drivers 322 as adedicated component for the display driver circuit board 320 having aspecial configuration including the no-terminal-formation region 327.

Fifth Embodiment

A fifth embodiment will be described, with reference to FIG. 13. Thisfifth embodiment describes a change from the first embodiment in theconfiguration of a substrate 421. Note that identical or substantiallyidentical structures and advantageous effects between the firstembodiment and this embodiment will not be elaborated upon.

As illustrated in FIG. 13, the substrate 421 according to thisembodiment does not include the notch 21B (see FIG. 4) described in thefirst embodiment. Hence, in this embodiment, the substrate 421 includesa no-terminal-formation region 427 between neighboring terminals 426.Such a configuration can also leave a large space for wiring to bepatterned on the substrate 421, beneficially achieving high definition.

Sixth Embodiment

A sixth embodiment will be described, with reference to FIG. 14. Thissixth embodiment describes a change from the first embodiment in theconfiguration of a substrate 521. Note that identical or substantiallyidentical structures and advantageous effects between the firstembodiment and this embodiment will not be elaborated upon.

As illustrated in FIG. 14, the substrate 521 according to thisembodiment includes a slit 521C instead of the notch 21B (see FIG. 4)described in the first embodiment. The slit 521, linearly extendingalong the Y-axis, is disposed on a substrate 521 between neighboringterminals 526. This slit 521 divides a join 521A of the substrate 521for each of the terminals 526. Hence, the substrate 521 has a portion,between the neighboring terminals 526, acting as a no-terminal-formationregion 527. The no-terminal-formation region 527 is divided by the slit521C into a portion including one of the terminals 526 and anotherportion including another one of the terminal 526. Such a configurationcan also leave a large space for wiring to be patterned on the substrate521, beneficially achieving high definition. In addition, theconfiguration makes it possible to reduce misalignment of a unitterminal 526A that might be caused by thermal expansion of the join521A.

Other Embodiments

The technique disclosed in this Specification shall not be limited tothat in the embodiments presented by the above descriptions and thedrawings. Alternatively, for example, embodiments below are alsoincluded in the scope of the technique.

(1) The substrates 21, 121, 421, and 521 may each include three or moreof the terminals 26, 126, 226, 326, 426, and 526. In such a case, theno-terminal-formation regions 27, 127, 227, 327, 427, and 527 are eachdisposed between the neighboring terminals 26, 126, 226, 326, 426, and526. The no-terminal-formation regions 27, 127, 227, 327, 427, and 527are fewer by one than the terminals 26, 126, 226, 326, 426, and 526 ofthe substrates 21, 121, 421, and 521. Specifically, if three eachterminals 26, 126, 226, 326, 426, and 526 are installed on thesubstrates 21, 121, 421, and 521, two each no-terminal-formation regions27, 127, 227, 327, 427, and 527 are provided.

(2) Other than the linear arrangement, a specific arrangement of theunit terminals 26A, 126A, 226A, and 526A of the terminals 26, 126, 226,326, 426, and 526 may include a staggered arrangement. In a similarmanner, the input terminals 22A and 222A, and output terminals 22Bincluded in the source drivers 22, 222, and 322, and the driver inputterminals 23 and the driver output terminals 24 included in thesubstrates 21, 121, 421, and 521 may be staggered.

(3) The specific number of the unit terminals 26A, 126A, 226A, and 526Aincluded in the terminals 26, 126, 226, 326, 426, and 526, and suppliedwith image signals may be changed as appropriate. In such a case, thenumber of output channels of the source driver 22, 222, and 322 maypreferably be changed as appropriate.

(4) The specific number of the input terminals 22A and 222A included inthe source drivers 22, 222, and 322 and receiving image signals may bethree or more groups, that is, six or more.

(5) Other than (3) and (4), the specific number of the various terminals22B, 23, 24, and 25 included in the substrates 21, 121, 421, and 521,and in the source drivers 22, 222, and 322 may be changed asappropriate.

(6) Three or more source drivers 22, 222, and 322 may be mounted on thesubstrates 21, 121, 421, and 521. In such a case, the number of thesource drivers 22, 222, and 322 to be mounted may be, but not limitedto, the same as that of the terminals 26, 126, 226, 326, 426, and 526 ofthe substrates 21, 121, 421, and 521.

(7) The specific number and arrangement of the common potentialterminals 26A2 and 126A2 in the substrates 21, 121, 421, and 521 may bechanged as appropriate.

(8) The specific distribution of the input signals to the source drivers22, 222, and 322 may be changed as appropriate.

(9) The specific number of the display driver circuit boards 20, 120,220, and 320 to be connected to the liquid crystal panels 10 and 110 towhich the display driver circuit boards 20, 120, 220, and 320 areconnected may be changed as appropriate to other than 12.

(10) The specific size and resolution of the liquid crystal panels 10and 110 to which the display driver circuit boards 20, 120, 220, and 320are connected may be changed as appropriate.

(11) The liquid crystal panels 10 and 110 to which the display drivercircuit boards 20, 120, 220, and 320 are connected may not only betransparent, but also be reflective and translucent.

(12) The planar shape of liquid crystal panels 10 and 110 to which thedisplay driver circuit boards 20, 120, 220, and 320 are connected mayinclude such shapes as a vertically oriented rectangle, a square, acircle, a semi-circle, an oval, an ellipse, and a trapezoid.

(13) The display driver circuit boards 20, 120, 220, and 320 may beconnected to other kinds of display panels (e.g., an organic EL panel,an electrophoretic display (EPD), and a micro-electro-mechanical-system(MEMS) display panel) than those of the liquid crystal panels 10 and110.

While there have been described what are at present considered to becertain embodiments of the invention, it will be understood that variousmodifications may be made thereto, and it is intended that the appendedclaims cover all such modifications as fall within the true spirit andscope of the invention.

What is claimed is:
 1. A display driver circuit board, comprising: asubstrate connected to a display panel; a display driver mounted on thesubstrate, and configured to process an input signal and output an imagesignal; and a plurality of terminals, each including a plurality of unitterminals arranged in a joint of the substrate, one of the plurality ofunit terminals supplying the image signal to the display panel, wherein:the substrate includes: the plurality of the terminals arranged atintervals in the joint; and a no-terminal-formation region providedbetween neighboring terminals that prevents the plurality of unitterminals from being formed; the display driver includes a plurality ofgroups of input terminals receiving the input signal, each of theplurality of groups including a pair of the plurality of inputterminals; “n” is a number of the plurality of unit terminals thatreceive the image signal to be output from the display driver; “m” is agroup number counted from a first group of the plurality of groups ofthe input terminals; the first group is sequentially supplied with a 0thto an (n−1) th input signal included in the input signal; and an m-thgroup of the plurality of groups is sequentially supplied with ann·(m−1) th to an (n·m−1) th input signal included in the input signal.2. The display driver circuit board according to claim 1, wherein thejoint is divided for each of the plurality of terminals.
 3. The displaydriver circuit board according to claim 2, wherein theno-terminal-formation region is a notch.
 4. The display driver circuitboard according to claim 1, wherein: each of the plurality of unitterminals includes a common potential terminal supplied with a commonpotential signal; and each common potential terminal is disposed at anend; of the joint, along an arrangement of the plurality of terminals,and in a portion of the joint bordering the no-terminal-formationregion.
 5. The display driver circuit board according to claim 1 whereinthe display driver is disposed across the no-terminal-formation regionalong an arrangement of the plurality of terminals.
 6. The displaydriver circuit board according to claim 1, further comprising a numberof display drivers the number equal to a number of the plurality ofterminals.
 7. A display device, comprising: the display driver circuitboard according to claim 1; and the display panel to which the displaydriver circuit board is connected.